1. Field of the Invention
The present invention relates to a heatable and/or coolable cylinder having a bearing axle pivotably mounted in a support and at least one stationary connection, the at least one stationary connection being coupled to the bearing axle for input and/or removal of at least one of heating and/or cooling medium through the at least one stationary connection and the bearing axle. A sealing device is provided between a rotating portion, e.g., a rotating cylinder body, the bearing axle, and/or at least one part rotating therewith, and a stationary portion, e.g., the support, the at least one stationary connection, and/or at least one other stationary part.
2. Discussion of the Background Information
In known cylinders, such as disclosed in, e.g., EP 0 499 597 B1 and DE 197 00 139 A1, sealing between a flange that is solidly coupled to the bearing axle and the stationary connection is provided by a piston ring with a carbon gasket that is mounted to be axially movable in the stationary connection and pressed against an annular sealing surface of the flange associated with the bearing axle. Pressure is generally applied by springs, and is reinforced by vapor pressure prevailing within the cylinder.
The temperature-associated allowances between the parts to be coupled to each other are compensated by such sealing.
However, due to the wear on the carbon seal that occurs during operation, it is essential that the condition of the seal be monitored. Consequently, seals such as these are generally only suitable for use between axially oriented sealing surfaces, i.e., sealing surfaces lying in a specific radial plane.
In addition to the relatively high axial forces acting on the bearing of the cylinder and the relatively fast wear, sealing arrangements in the prior art have the disadvantage of relatively expensive design.
Moreover, known radial sealing rings are inadequate or unusable due to the usual temperatures in dryer cylinders of paper or cardboard producing machines, e.g., between approximately 80 and 230.degree. C.